1. Field of the Invention
The present invention relates to a camera in which opening and closure of a shutter are controlled by an electrical signal and, more particularly, to a camera in which feeding of a film is driven by an electric motor.
2. Description of the Prior Art
In cameras using a roll film, there are generally three kinds of cases for feeding the film installed in the camera. The first case relates to winding-up in which the film is fed on a one-frame unit basis each time the photographing operation is executed. The second case relates to rewinding in which the film is fed into a cartridge or magazine after completion of exposure. The third case relates to initial winding in which when the film is installed into a camera, the reader portion of the film is fed and the unexposed frames are continuously wound up without photographing so as to face the photographing opening. There has been well-known the camera in which those film feeding operations, namely, the winding-up, rewinding and initial winding operations are respectively added to the operation sequence of the camera and are automatically controlled. In such a well-known camera, the winding-up is performed in response to generation of an exposure completion signal representing that the period of time required until the shutter is completely closed from the timing of generation of a closing start signal of the shutter has elapsed; the rewinding is carried out in response to a film end signal which is generated after completion of exposure of all frames of the film or to the manual setting operation for rewinding; and the initial winding is executed in response to the closure of the back cover of the camera which is performed after installing an unused film or to the depression of the release button which is performed after the back cover was closed.
In such a kind of cameras, there can occur accidents such that the shutter is not closed in spite of the fact that the shutter closing start signal has been generated and the shutter is opened in spite of the fact that no shutter opening start signal has been generated.
In the case where such accidents have occurred, if the winding-up or rewinding is started in accordance with the foregoing operations, the film after completion of the photographing will be again exposed and ruined. On one hand, if initial winding is started, the first frame will have been unnecessarily exposed. If the user continues the photographing operation in this state without being aware of those accidents, all of the frames photographed after the accident will have become spoilt.